It’s possible that I shall make an ass of myself. But in that case one can always get out of it with a little dialectic. I have, of course, so worded my proposition as to be right either way (K.Marx, Letter to F.Engels on the Indian Mutiny)
Saturday, June 27, 2020
The geological record of mud deposits
A study by the University of the Basque Country (UPV/EHU) confirms that the sediments had accumulated at an approximate rate of one millimetre per year in the area of the Basque Mud Patch
IMAGE: RESEARCHER IN THE UPV/EHU'S DEPARTMENT OF MINERALOGY AND PETROLOGY view more
CREDIT: UPV/EHU
UNIVERSITY OF THE BASQUE COUNTRY
The nature of the sediments on the Basque continental shelf is very heterogeneous. From the point of view of distribution, two clearly differentiated sectors can be picked out in terms of grain size. "In the area of Bizkaia medium to coarse-sized sands predominate, whereas on the coast of Gipuzkoa there is a predomination of deposits of very fine sand, silts and clays, currently known as the Basque Mud Patch (BMP)," explained Maria Jesus Irabien, researcher in the UPV/EHU's Department of Mineralogy and Petrology.
"This mud patch has an irregular surface area of approximately 680 km2. Metals and contaminants, in general, are more likely to build up in this type of muddy material. So if what we are aiming to do is study anthropogenic, industrial or human influence, it is necessary to explore the mud patch in the area of Gipuzkoa," said the researcher in the Harea: Coastal Geology group of the UPV/EHU.
So, as Irabien pointed out, "we analysed three cores (19-46 cm deep) from a multidisciplinary perspective that includes the analysis of various metals, foraminifera (small organisms characterised by a shell or chalky conch), pollen and various natural and artificial isotopes".
"The results obtained have made it possible to calculate that the sediments build up at an approximate rate of one millimetre per year. An increase in the concentrations of metals from the end of the 19th century onwards can also be observed, showing that the influence of industrialization and human activity taking place in the Basque Country extends to the marine environment. In the case of lead (Pb), for example, the content in the most recent samples is five times higher than in that recorded in the past. However, the foraminifera are not affected by this contamination. Finally, the pollen analysis displays a growing trend in conifers and a reduction in indigenous species (Deciduous Quercus), possibly as a result of reforestation," highlighted the researcher of the Harea: Coastal Geology group of the UPV/EHU.
"The results confirm that the influence of coastal anthropogenic activities extends to the adjacent shelf where muddy deposits are likely to act as a trap for contaminants," said Irabien.
The researcher stresses "the importance of continuing to make interpretations of this type in marine depths to get to know marine evolution from a historical perspective. It is clear that human activity is exerting a significant influence on the coast, too; the only advantage that all this has is knowing we can stop," concluded María Jesús Irabien.
###
Additional information
The Harea-Coastal Geology research group of the UPV/EHU conducts work based on a multidisciplinary geological approach (sedimentology, geochemistry, micropalaeontology, topography, radiometric dating) for the purpose of characterising processes of natural and anthropogenic origin responsible for the environmental transformation of the coastal area during the most recent climate cycle.
International team of scientists warns of increasing threats posed by invasive species
UNIVERSITY OF RHODE ISLAND
KINGSTON, R.I. - June 26, 2020 -- In a new study, scientists from around the world - including a professor at the University of Rhode Island - warn that the threats posed by invasive alien species are increasing. They say that urgent action is required to prevent, detect and control invaders at both local and global levels.
Alien species are plants, animals and microbes that are introduced by people, accidentally or intentionally, into areas where they do not naturally occur. Many of them thrive, spreading widely with harmful effects on the environment, economy, or human health.
The study, published in the journal Biological Reviews, was carried out by a team of researchers from 13 countries across Africa, Asia, Australasia, Europe, and North and South America. It states that the number of invasive alien species is increasing rapidly, with more than 18,000 currently listed around the world.
According to Laura Meyerson, URI associate professor of natural resources science, the escalation in biological invasions is due to the increase in the number and variety of pathways along which species spread, and to the increasing volume of traffic associated with those pathways. For example, she notes the role played by emerging pathways such as the online trade in unusual pets and the transport of species across oceans on rafts of plastic.
The researchers note that the scale of the problem is enormous. A 2017 analysis of global extinctions revealed that alien species contributed to 25 percent of plant extinctions and 33 percent of terrestrial and freshwater animal extinctions. Meanwhile, annual environmental losses caused by introduced species in the United States, United Kingdom, Australia, South Africa, India and Brazil have been calculated at more than $100 billion.
The study also shows how drivers of global change, such as climate change, land-use change, and international trade, are exacerbating the impacts of biological invasions. Species transported through shipping can now thrive in new regions, for instance, owing to climate warming. And the permanent opening of the Arctic Ocean due to global warming is allowing marine species to move between the Atlantic and Pacific Oceans.
The research paper is part of an initiative called World Scientists' Warning to Humanity: A Second Notice, which calls for urgent change in stewardship of the Earth and the life on it. The first notice, in 1992, was supported by 1,700 eminent scientists from around the globe who warned that humanity was on a collision course with the rest of the natural world. Twenty-five years later, a follow-up evaluation supported by 15,000 scientists declared that humanity had failed to make sufficient progress in dealing with the environmental challenges. Indeed, they found that most of these problems had worsened.
The authors of the new paper stress that biological invasions can be managed and mitigated. They point to approaches that are working around the world and make specific recommendations for improved management. For example, the introduction of more stringent border controls, including X-ray machines and detector dogs, has led to a progressive decline in the rate of fungal plant pathogens entering New Zealand.
Professor Petr Pyšek of the Czech Academy of Sciences and Charles University in Prague, lead author of the study, said: "As our knowledge about invasive alien species increases, the problems associated with biological invasions are becoming clearer. The threats posed by invasive alien species to our environment, our economies and our health are very serious, and getting worse. Policy makers and the public need to prioritize actions to stem invasions and their impacts."
Professor David Richardson of the Centre for Invasion Biology at Stellenbosch University in South Africa, the other lead author, added: "Nations such as Australia and New Zealand have made biosecurity a national priority. South Africa has invested heavily in a massive national programme focussed on reducing the negative impacts of widespread invaders on ecosystem services, especially the delivery of water from catchments invaded by alien trees. But action is needed more widely at both national and international levels in order to tackle the challenges effectively."
Meyerson, who contributed to the paper and is leading the chapter on trends in invasions for a report on invasive alien species for the Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services, said, "It has been so exciting to see developments in our knowledge and understanding of biological invasions in recent decades, achieved through truly inspiring global collaborations. It is so important that we continue to share our knowledge and engage with relevant stakeholders across sectors and borders."
###
New compounds from starfish of Kuril basin show efficacy against cancer cells.
FAR EASTERN FEDERAL UNIVERSITY
IMAGE: STARFISH CERAMASTER PATAGONICUS TRAWLED FROM A DEPTH OF 170 METERS BY R/V VESTERAALEN NORTH OF RAT ISLAND, ALEUTIANS ON 7/6/2004 DURING NOAA/NMFS TRAWL SURVEY. (RADIUS OF RAYS ABOUT 40 MM.)... view more
CREDIT: BILL FRANK, WWW.JAXSHELLS.ORG
Russian scientists from Far Eastern Federal University (FEFU), G. B. Elyakov Pacific Institute of Bioorganic Chemistry (PIBOC FEB RAS), and A.V. Zhirmunsky National Scientific Center for Marine Biology (NSCMB FEB RAS) have discovered four new steroid substances which target cells of human breast cancer, and colorectal carcinoma. They were extracted from the starfish Ceramaster patagonicus, a Kuril basin seabed dweller. A related article appears in Marine Drugs.
The discovery made due to the joint expedition of scientists of FEFU and Far Eastern Branch of Russian Science Academy (FEB RAS) to the Kuril Islands at the "Academic Oparin" research vessel.
Four new compounds belong to non-typical derivatives of polar steroids with residual tails of fatty acids in the molecular structure. According to scientists, these compounds may be responsible in the body of starfish for the delivery of nutrients from the digestive tract to peripheral cells, acting alike bile acids in the human stomach. Previously, only one such compound was isolated from starfish.
In the study, scientists point out a pronounce anticancer effect of the unusual molecules. At the same time, researchers suggest that, due to their steroid nature, one can potentially consider such substances from starfish as blockers of neurodegenerative diseases (Alzheimer's disease, etc.), since they help nerve cells survive distress like, for example, low levels of oxygen and glucose.
"Importantly, the new steroid compounds from starfish curb the reproduction of cancer cells in non-toxic concentrations. That gives a hope that new substances will not kill healthy body cells, and makes a promise for further study and testing," says Timofey Malyarenko, Ph.D., associate professor of the Department of Bioorganic Chemistry and Biotechnology, FEFU School of Natural Sciences, Deputy Director for Science and Senior Researcher at Laboratory of Chemistry of Marine Natural Compounds in PIBOC FEB RAS. "It is interesting that these compounds had been found almost by accident when I was looking for new lipid molecules or fats of marine origin in the starfish extract. During the separation of substances on chromatographic plates (TLC), curious spots were detected. Having studied them, we established the structures of four new derivatives of polar steroids with fatty acids. There are five of them in the world now."
According to the scientist, the next step of the study could be the production of molecules with increased therapeutic properties based on steroid compounds. In addition, it is probable to scrutinize the new compounds to reveal the most active molecules responsible for the drug effect. It would give the opportunity to look for similar compounds in other types of starfishes. Potentially, these future substances will be even more effective.
FEFU University runs a priority project for a comprehensive study of the biological resources of the World Ocean. Among the aims of the project is to pick new biologically active marine substances and cast them for the roles of drugs of the future.
###
The Russian Science Foundation (RSF) supported the study. Grant No. 18-74-10028 "Biologically active metabolites of marine invertebrates as promising drugs in the complex therapy of cancer".
Ancient Maya reservoirs contained toxic pollution
Mercury, algae made water undrinkable in heart of city
UNIVERSITY OF CINCINNATI
IMAGE: THE ANCIENT CITY OF TIKAL RISES ABOVE THE RAINFOREST IN NORTHERN GUATEMALA. view more
CREDIT: DAVID LENTZ/UC
Reservoirs in the heart of an ancient Maya city were so polluted with mercury and algae that the water likely was undrinkable.
Researchers from the University of Cincinnati found toxic levels of pollution in two central reservoirs in Tikal, an ancient Maya city that dates back to the third century B.C. in what is now northern Guatemala.
UC's findings suggest droughts in the ninth century likely contributed to the depopulation and eventual abandonment of the city.
"The conversion of Tikal's central reservoirs from life-sustaining to sickness-inducing places would have both practically and symbolically helped to bring about the abandonment of this magnificent city," the study concluded.
A geochemical analysis found that two reservoirs nearest the city palace and temple contained toxic levels of mercury that UC researchers traced back to a pigment the Maya used to adorn buildings, clayware and other goods. During rainstorms, mercury in the pigment leached into the reservoirs where it settled in layers of sediment over the years.
But the former inhabitants of this city, made famous by its towering stone temples and architecture, had ample potable water from nearby reservoirs that remained uncontaminated, UC researchers found.
The study was published in the Nature journal Scientific Reports.
UC's diverse team was composed of anthropologists, geographers, botanists, biologists and chemists. They examined layers of sediment dating back to the ninth century when Tikal was a flourishing city.
Previously, UC researchers found that the soils around Tikal during the ninth century were extremely fertile and traced the source to frequent volcanic eruptions that enriched the soil of the Yucatan Peninsula.
"Archaeologists and anthropologists have been trying to figure out what happened to the Maya for 100 years," said David Lentz, a UC professor of biological sciences and lead author of the study.
For the latest study, UC researchers sampled sediment at 10 reservoirs within the city and conducted an analysis on ancient DNA found in the stratified clay of four of them.
Sediment from the reservoirs nearest Tikal's central temple and palace showed evidence of toxic algae called cyanobacteria. Consuming this water, particularly during droughts, would have made people sick even if the water were boiled, Lentz said.
"We found two types of blue-green algae that produce toxic chemicals. The bad thing about these is they're resistant to boiling. It made water in these reservoirs toxic to drink," Lentz said.
UC researchers said it is possible but unlikely the Maya used these reservoirs for drinking, cooking or irrigation.
"The water would have looked nasty. It would have tasted nasty," said Kenneth Tankersley, an associate professor of anthropology in UC's College of Arts and Sciences. "There would have been these big algae blooms. Nobody would have wanted to drink that water."
But researchers found no evidence of the same pollutants in sediments from more distant reservoirs called Perdido and Corriental, which likely provided drinking water for city residents during the ninth century.
Today, Tikal is a national park and a UNESCO World Heritage site. Researchers believe a combination of economic, political and social factors prompted people to leave the city and its adjacent farms. But the climate no doubt played a role, too, Lentz said.
"They have a prolonged dry season. For part of the year, it's rainy and wet. The rest of the year, it's really dry with almost no rainfall. So they had a problem finding water," Lentz said.
Co-author Trinity Hamilton, now an assistant professor of biology at the University of Minnesota, worked on the analysis of ancient DNA from algae that sank to the reservoir bottom and was buried by centuries of accumulated sediment.
"Typically, when we see a lot of cyanobacteria in freshwater, we think of harmful algal blooms that impact water quality," Hamilton said.
Finding some reservoirs that were polluted and others that were not suggests the ancient Maya used them for different purposes, she said.
Reservoirs near the temple and palace likely would have been impressive landmarks, much like the reflecting pool at the National Mall is today.
"It would have been a magnificent sight to see these brightly painted buildings reflected off the surface of these reservoirs," said co-author Nicholas Dunning, head of geography in UC's College of Arts and Sciences.
"The Maya rulers conferred to themselves, among other things, the attribute of being able to control water. They had a special relationship to the rain gods," Dunning said. "So the reservoir would have been a pretty potent symbol."
UC's Tankersley said one popular pigment used on plaster walls and in ceremonial burials was derived from cinnabar, a red-colored mineral composed of mercury sulfide that the Maya mined from a nearby volcanic feature known as the Todos Santos Formation.
A close examination of the reservoir sediment using a technique called energy dispersive X-ray fluorescence spectrometry found that mercury did not leach into the water from the underlying bedrock. Likewise, Tankersley said, UC ruled out another potential source of mercury -- volcanic ash that fell across Central America during the frequent eruptions. The absence of mercury in other nearby reservoirs where ash would have fallen ruled out volcanoes as the culprit.
Instead, Tankersley said, people were to blame.
"That means the mercury has to be anthropogenic," Tankersley said.
With its bright red color, cinnabar was commonly used as a paint or pigment across Central America at the time.
"Color was important in the ancient Maya world. They used it in their murals. They painted the plaster red. They used it in burials and combined it with iron oxide to get different shades," Tankersley said.
"We were able to find a mineral fingerprint that showed beyond a reasonable doubt that the mercury in the water originated from cinnabar," he said.
Tankersley said ancient Maya cities such as Tikal continue to captivate researchers because of the ingenuity, cooperation and sophistication required to thrive in this tropical land of extremes.
"When I look at the ancient Maya, I see a very sophisticated people with a very rich culture," Tankersley said.
UC's team is planning to return to the Yucatan Peninsula to pursue more answers about this remarkable period of human civilization.
###
Air pollution could help London transport planners fight COVID-19
UNIVERSITY OF BIRMINGHAM
Measuring air quality across London could help fight COVID-19 by providing a rapid means of deciding whether to reduce public transport movement - given strong links between exposure to air pollution and COVID-19 transmission, a new study reveals.
Analysis of air pollution, COVID-19 cases and fatality rates in London demonstrates a connection between increased levels of nitrogen dioxide (NO2) and particulate matter (PM2.5) and higher risk of viral transmission.
Scientists at the Universities of Birmingham and Cambridge say that this shows air pollution could be used as an indicator to rapidly identify vulnerable parts of a city such as London - informing decisions to suspend or reduce operation of buses, trains and Underground.
Researchers have published their findings today in Science of The Total Environment, highlighting that using public transport in the UK during a pandemic outbreak has a six-fold increased risk of contracting an acute respiratory infection.
City boroughs with access to London Underground interchange stations also have higher pandemic case rates as users are exposed to a higher number of individuals compared to through stations.
Report author Dr Ajit Singh, from the University of Birmingham, commented: "Short-term exposure to NO2 and PM2.5is significantly linked to an increased risk of contracting and dying from COVID-19. Exposure to such air pollutants can compromise lung function and increase risk of death from the virus.
"Levels of airborne PM2.5in the London Underground during summer are often several times higher than other transport environments such as cycling, buses or cars. We recommend a strategy that tailors the level of public transport activity in cities like London according to COVID-19 vulnerability based on air pollution levels across the city.
"This could help decision-makers take the right measures to counter COVID-19 in London - for example deploying transport staff and arranging dedicated services for key workers."
Scientists have earlier found the greatest PM2.5concentrations across the London Underground network on the Victoria Line (16 times higher than the roadside environment), followed by the Northern, Bakerloo and Piccadilly lines.
Routine cleaning and maintenance of the London Underground ranges from litter removal to preventing safety incidents rather than reducing PM concentrations.
Co-author Dr Manu Sasidharan, of the University of Cambridge, commented: "Human-mobility reduction measures provide the greatest benefit in the fight against COVID-19. We need to balance the public health benefits of closing public transport during a pandemic against the socio-economic impacts of reducing mobility.
"Determining the vulnerability of city regions to coronavirus might help to achieve such trade-offs - air pollution levels can serve as one of the indicators to assess this vulnerability."
The number of positive COVID-19 cases considered in the study were only those reported at hospitals - it does not include people self-isolating due to COVID-19.
###
For more information, please contact Tony Moran, International Communications Manager, University of Birmingham on +44 (0)782 783 2312 or t.moran@bham.ac.uk. For out-of-hours enquiries, please call +44 (0) 7789 921 165.
Notes to Editors
* The University of Birmingham is ranked amongst the world's top 100 institutions, its work brings people from across the world to Birmingham, including researchers and teachers and more than 6,500 international students from over 150 countries.
* 'A vulnerability-based approach to human-mobility reduction for countering COVID-19 transmission in London while considering local air quality' - Manu Sasidharan, Ajit Singh, Mehran Eskandari Torbaghan and Ajith Kumar Parlikad is published in Science of The Total Environment.
Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy o
Traffic density, wind and air stratification influence concentrations of air pollutant NO2
Leipzig researchers use a calculation method to remove weather influences from air pollution data
LEIBNIZ INSTITUTE FOR TROPOSPHERIC RESEARCH (TROPOS)
IMAGE: TRAFFIC DENSITY, WIND AND AIR STRATIFICATION INFLUENCE THE POLLUTION WITH THE AIR POLLUTANT NITROGEN DIOXIDE, ACCORDING TO THE CONCLUSION OF A TROPOS STUDY COMMISSIONED BY THE LFULG. view more
CREDIT: BURKHARD LEHMANN, LFULG
Leipzig/Dresden. In connection with the effects of the COVID-19 pandemic, satellite measurements made headlines showing how much the air pollutant nitrogen dioxide (NO2) had decreased in China and northern Italy. In Germany, traffic density is the most important factor. However, weather also has an influence on NO2 concentrations, according to a study by the Leibniz Institute for Tropospheric Research (TROPOS), which evaluated the influence of weather conditions on nitrogen dioxide concentrations in Saxony 2015 to 2018 on behalf of the Saxon State Office for Environment, Agriculture and Geology (LfULG). It was shown that wind speed and the height of the lowest air layer are the most important factors that determine how much pollutants can accumulate locally.
In order to determine the influence of various weather factors on air quality, the team used a statistical method that allows meteorological fluctuations to be mathematically removed from long-term measurements. The air quality fluctuates, in some cases very strongly, due to different emissions and the influence of the weather. Until now, however, it has been difficult to estimate, what share legal measures such as low emission zones or diesel driving bans have and what share the weather influences have in the actual air quality? With the method used, this will be easier in the future.
Nitrogen dioxide (NO2) is an irritant gas which attacks the mucous membrane of the respiratory tract, causes inflammatory reactions as an oxidant and increases the effect of other air pollutants. As a precursor substance, it can also contribute to the formation of particulate matter. Limit values have been set in the EU to protect the population: For nitrogen dioxide, an annual average value of 40 micrograms per cubic metre of air applies (μg/m³). To protect the health of the population, measures must be taken if these limit values are not complied with. In 2018/2019, for example, various measures were taken in Germany, ranging from a reduction in the number of lanes (e.g. in Leipzig) to driving bans for older diesel vehicles (e.g. in Stuttgart).
To evaluate the effectiveness of such measures, it would be helpful to determine the exact influence of weather conditions. The Saxon State Office for Environment, Agriculture and Geology (LfULG) therefore commissioned TROPOS to carry out a study on the influence of weather factors on NO2 concentrations and provided its measurement data from the Saxon air quality measurement network and meteorological data for this purpose. The researchers were thus able to evaluate data from 29 stations in Saxony over a period of four years, which represent a cross-section of air pollution - from stations at traffic centres to urban and rural background stations and stations on the ridge of the Erzgebirge mountains. They also calculated the height of the lowest layer in the atmosphere and incorporated data from traffic counting stations in Leipzig and Dresden into the study. A method from the field of machine learning was used for the statistical modelling, the application of which in the field of air quality was first published by British researchers in 2009.
In this way, the study was able to demonstrate that the traffic density at all traffic stations is most significantly responsible for nitrogen oxide concentrations. However, two weather parameters also have a significant influence on nitrogen dioxide concentrations: wind speed and the height of the so-called mixing layer. The latter is a meteorological parameter that indicates the height to which the lowest layer of air, where the emissions mix, extends. "It was also shown that high humidity can also reduce the concentration of nitrogen dioxide, which could be due to the fact that the pollutants deposit more strongly on moist surfaces. However, the exact causes are still unclear," says Dominik van Pinxteren.
The statistical analysis has also enabled the researchers to remove the influence of the weather from the time series of pollutant concentrations: Adjusted for the weather, the concentration of nitrogen oxides (NOx) decreased by a total of 10 micrograms per cubic meter between 2015 and 2018 on average over all traffic stations in Saxony. In urban and rural areas and on the ridge of the Erzgebirge, however, NOx concentrations tend to remain at the same level. Even though there have been some improvements in air quality in recent years, there are good scientific arguments for further reducing air pollution.
In a way, this also applies to premature conclusions from the corona crisis: in order to find out how strong the influence of the initial restrictions on air quality actually was, the influence of the weather would have to be statistically removed in a longer series of measurements. To this end, investigations for the Leipzig area are currently underway at TROPOS, as is a Europe-wide study of the EU research infrastructure for short-lived atmospheric constituents such as aerosol, clouds and trace gases (ACTRIS), the German contribution to which is coordinated by TROPOS. Tilo Arnhold
###
Publication:
Dominik van Pinxteren, Sebastian Düsing, Alfred Wiedensohler, Hartmut Herrmann (2020): Meteorological influences on nitrogen dioxide: Influence of weather conditions and weathering on nitrogen dioxide concentrations in outdoor air 2015 to 2018. Series of publications of the LfULG, issue 2/2020 (in German only) https://publikationen.sachsen.de/bdb/artikel/35043
This study was commissioned by the State Office for Environment, Agriculture and Geology (LfULG).
More evidence of causal link between air pollution and early death
Study of more than 68 million older Americans using state-of-the-art analyses suggests that US air pollution standards are not protective enough
HARVARD T.H. CHAN SCHOOL OF PUBLIC HEALTH
Boston, MA - Strengthening U.S. air quality standards for fine particulate pollution to be in compliance with current World Health Association (WHO) guidelines could save more than 140,000 lives over the course of a decade, according to a new study from Harvard T.H. Chan School of Public Health.
The study, published June 26, 2020 in Sciences Advances, provides the most comprehensive evidence to date of the causal link between long-term exposure to fine particulate (PM2.5) air pollution and premature death, according to the authors.
"Our new study included the largest-ever dataset of older Americans and used multiple analytical methods, including statistical methods for causal inference, to show that current U.S. standards for PM2.5 concentrations are not protective enough and should be lowered to ensure that vulnerable populations, such as the elderly, are safe," said doctoral student Xiao Wu, a co-author of the study.
The new research builds on a 2017 study that showed that long-term exposure to PM2.5 pollution and ozone, even at levels below current U.S. air quality standards, increases the risk of premature death among the elderly in the U.S.
For the new study, researchers looked at 16 years' worth of data from 68.5 million Medicare enrollees--97% of Americans over the age of 65--adjusting for factors such as body mass index, smoking, ethnicity, income, and education. They matched participants' zip codes with air pollution data gathered from locations across the U.S. In estimating daily levels of PM2.5 air pollution for each zip code, the researchers also took into account satellite data, land-use information, weather variables, and other factors. They used two traditional statistical approaches as well as three state-of-the-art approaches aimed at teasing out cause and effect.
Results were consistent across all five different types of analyses, offering what authors called "the most robust and reproducible evidence to date" on the causal link between exposure to PM2.5 and mortality among Medicare enrollees--even at levels below the current U.S. air quality standard of 12 μg/m3 (12 micrograms per cubic meter) per year.
The authors found that an annual decrease of 10 μg/m3 in PM2.5 pollution would lead to a 6%-7% decrease in mortality risk. Based on that finding, they estimated that if the U.S. lowered its annual PM2.5 standard to 10 μg/m3--the WHO annual guideline--143,257 lives would be saved in one decade.
The authors included additional analyses focused on causation, which address criticisms that traditional analytical methods are not sufficient to inform revisions of national air quality standards. The new analyses enabled the researchers, in effect, to mimic a randomized study--considered the gold standard in assessing causality--thereby strengthening the finding of a link between air pollution and early death.
"The Environmental Protection Agency has proposed retaining current national air quality standards. But, as our new analysis shows, the current standards aren't protective enough, and strengthening them could save thousands of lives. With the public comment period for the EPA proposal ending on June 29, we hope our results can inform policymakers' decisions about potentially updating the standards," said co-author Francesca Dominici, Clarence James Gamble Professor of Biostatistics, Population, and Data Science.
###
Other Harvard Chan School co-authors of the study included research scientist Danielle Braun and Joel Schwartz, professor of environmental epidemiology.
Funding for the study came from NIH grants R01 ES024332-01A1, P50 MD010428, R21 ES024012, R01 ES026217, R01 ES028033, MD012769, R01 ES030616, and P30 ES09089; HEI grant 4953-RFA14-3/16-4; and USEPA grants 83587201-0 and RD-83479801.
"Evaluating the Impact of Long-term Exposure to Fine Particulate Matter on Mortality Among the Elderly," Xiao Wu, Danielle Braun, Marianthi-Anna Kioumourtzoglou, Francesca Dominici, Science Advances, June 26, 2020, doi: 10.1126/sciadv.aba5692.
Visit the Harvard Chan School website for the latest news, press releases, and multimedia offerings.
Harvard T.H. Chan School of Public Health brings together dedicated experts from many disciplines to educate new generations of global health leaders and produce powerful ideas that improve the lives and health of people everywhere. As a community of leading scientists, educators, and students, we work together to take innovative ideas from the laboratory to people's lives--not only making scientific breakthroughs, but also working to change individual behaviors, public policies, and health care practices. Each year, more than 400 faculty members at Harvard Chan School teach 1,000-plus full-time students from around the world and train thousands more through online and executive education courses. Founded in 1913 as the Harvard-MIT School of Health Officers, the School is recognized as America's oldest professional training program in public health.
Disclaimer: AAAS and EurekAlert! are not responsible
Study finds strong evidence for a causal link between long-term exposure to fine air particles and greater mortality in elderly Americans
Evaluating the impact of long-term exposure to fine particulate matter on mortality among the elderly
AMERICAN ASSOCIATION FOR THE ADVANCEMENT OF SCIENCE
A new analysis of 16 years of publicly accessible health data on 68.5 million Medicare enrollees provides broad evidence that long-term exposure to fine particles in the air - even at levels below current EPA standards - leads to increased mortality rates among the elderly. Based on the results of five complementary statistical models, including three causal inference methods, the researchers estimate that if the EPA had lowered the air quality standard for fine particle concentration from 12 μg/m3 down to the WHO guideline of 10 μg/m3, more than 140,000 lives might have been saved within one decade. "Our findings provide the strongest evidence to date that current national air quality standards aren't sufficiently protective of Americans' health," said corresponding author Francesca Dominici. "Now, in the middle of a pandemic that attacks our lungs and makes us unable to breathe, it is irresponsible to roll back environmental policies," she added. The new study is likely to inform national discussions around updating air quality standards, for example, the National Ambient Air Quality Standards by the EPA.
A number of studies have documented a strong correlation between long-term exposure to fine particulate and greater human mortality, but some concern has remained about the causal nature of the evidence, and whether it is sufficient to inform revisions to air quality standards. Some scientists argue that modern causal inference methods can provide such evidence, using the right data. "Causal inference can quantify and visualize how close our data are to approximating a randomized controlled study, the gold standard for assessing causation," said the study's lead author Xiao Wu. Analyzing a massive dataset through five distinct approaches, including two traditional statistical methods and three causal inference methods, Wu and colleagues derived broad evidence consistent with a causal link between long-term particulate exposure and mortality. Modeling a 10 μg/m3 decrease of fine particle concentration between 2000 and 2016 resulted in a 6% to 7% decrease in mortality risk. Based on their model results, the researchers estimated that more than 140,000 lives might have been saved if the current U.S. standard for fine particle concentration had been lowered to 10 μg/m3 between 2007 and 2016. The authors emphasize the urgent need to modify particulate concentration levels to help protect elderly individuals with respiratory diseases living in polluted areas.
Children more resilient against coronavirus, study reveals
Texas team reviews 131 studies of children from 26 countries
UNIVERSITY OF TEXAS HEALTH SCIENCE CENTER AT SAN ANTONIO
IMAGE: ALVARO MOREIRA, MD, MSC, OF THE LONG SCHOOL OF MEDICINE AT UT HEALTH SAN ANTONIO, LED A STUDY TEAM THAT FOUND CHILDREN INFECTED WITH THE CORONAVIRUS FARED BETTER THAN ADULTS.... view more
CREDIT: UT HEALTH SAN ANTONIO
SAN ANTONIO - The majority of children with COVID-19 in 26 countries fared well clinically compared to adults during the first four months of the pandemic, a newly released study shows.
Researchers from the Long School of Medicine at The University of Texas Health Science Center at San Antonio prepared the study, which is the largest systematic review to date of children and young adults with COVID-19. EClinicalMedicine, a journal of The Lancet, on June 26 published the results, which cover studies published between Jan. 24 and May 14.
Among the findings:
19% of the pediatric population with COVID-19 had no symptoms.
21% exhibited patchy lesions on lung X-rays.
5.6% suffered from co-infections, such as flu, on top of COVID-19.
3.3% were admitted to intensive care units.
Seven deaths were reported.
"Our data is compiled from 131 studies and encompasses 7,780 patients who span the pediatric age spectrum," said study senior author Alvaro Moreira, MD, MSc, assistant professor of pediatrics at UT Health San Antonio and a fellowship-trained neonatologist.
"In the study we report the most common symptoms, quantify laboratory findings and describe imaging characteristics of children with COVID-19," Dr. Moreira said. "Furthermore, we summarize treatments that were administered and offer an initial glimpse of a handful of patients who met the U.S. Centers for Disease Control and Prevention (CDC) criteria for multisystem inflammatory syndrome in children."
Symptoms
The most frequent symptoms, similar to the adult population, were fever and cough. Those were found in 59% and 56% of the pediatric population.
In 233 individuals, a past medical history was noted, and among this group, 152 were children with compromised immune systems or who had underlying respiratory or cardiac disease.
The number of children with excellent outcomes surprised the research team. "Although we are hearing about severe forms of the disease in children, this is occurring in very rare circumstances," Dr. Moreira said.
The majority of journal articles were from China. The largest study that was included was a case series of 2,572 patients reported by the U.S. CDC COVID-19 team.
Laboratory measures that were consistently abnormal in pediatric COVID-19 patients included inflammatory markers such as creatine kinase, interleukin-6 and procalcitonin.
Few severe cases
Thankfully, only a small number of patients met inclusion for multisystem inflammatory syndrome in children. Their disease paralleled the extreme forms of COVID-19 seen in adults.
"Children with systemic inflammation had a significant decrease in the amount of lymphocytes in their blood," Dr. Moreira said. "COVID-positive children who didn't have the extreme form of the disease had 42% lymphocytes in their blood, versus 11% in children with the multisystem syndrome."
Lymphocytes are one of the main types of immune cells in the body.
Kidney failure was seen in nine pediatric patients, liver failure also in nine and shock in 19. Mechanical ventilation was required by 42 patients.
The study does not take into consideration a new surge of patients in New York, England and Italy where specialists are now starting to see children with multisystem inflammatory syndrome, Dr. Moreira said.
###
In addition to Dr. Moreira, the team consists of two study co-first authors who are medical students in the Long School of Medicine; a pediatric intensive care fellow at Texas Children's Hospital in Houston; undergraduate students from Texas A&M, The University of Texas at San Antonio and Cottey College; a student accepted into the McGovern Medical School at UTHealth in Houston; and a San Antonio high school student.
COVID-19 in 7,780 pediatric patients A systematic review
Ansel Hoang, Kevin Chorath, Axel Moreira, Mary Evans, Finn Burmeister-Morton, Fiona Burmeister, Rija Naqvi, Matthew Petershack, Alvaro Moreira, MD, MSc
The Long School of Medicine at The University of Texas Health Science Center at San Antonio is named for Texas philanthropists Joe R. and Teresa Lozano Long. The school is the largest educator of physicians in South Texas, many of whom remain in San Antonio and the region to practice medicine. The school teaches more than 900 students and trains 800 residents each year. As a beacon of multicultural sensitivity, the school annually exceeds the national medical school average of Hispanic students enrolled. The school's clinical practice is the largest multidisciplinary medical group in South Texas with 850 physicians in more than 100 specialties. The school has a highly productive research enterprise where world leaders in Alzheimer's disease, diabetes, cancer, aging, heart disease, kidney disease and many other fields are translating molecular discoveries into new therapies. The Long School of Medicine is home to a National Cancer Institute-designated cancer center known for prolific clinical trials and drug development programs, as well as a world-renowned center for aging and related diseases.
The University of Texas Health Science Center at San Antonio, also referred to as UT Health San Antonio, is one of the country's leading health sciences universities and is designated as a Hispanic-Serving Institution by the U.S. Department of Education. With missions of teaching, research, patient care and community engagement, its schools of medicine, nursing, dentistry, health professions and graduate biomedical sciences have graduated more than 37,000 alumni who are leading change, advancing their fields, and renewing hope for patients and their families throughout South Texas and the world. To learn about the many ways "We make lives better®," visit http://www.uthscsa.edu.
To see how we are battling COVID-19, read inspiring stories on Impact.
Life in the galaxy: maybe this is as good as it gets?
GOLDSCHMIDT CONFERENCE
IMAGE: GALAXY M51 IS A SPIRAL GALAXY, ABOUT 30 MILLION LIGHT YEARS AWAY, THAT IS IN THE PROCESS OF MERGING WITH A SMALLER GALAXY SEEN TO ITS UPPER LEFT. view more
CREDIT: IMAGE CREDIT: X-RAY: NASA/CXC/SAO; OPTICAL: DETLEF HARTMANN; INFRARED: COURTESY NASA/JPL-CALTECH. HI-DEFINITION IMAGE AVAILABLE AT HTTPS://WWW.NASA.GOV/MISSION_PAGES/CHANDRA/MULTIMEDIA/SPIRAL-GALAXY-M51.HTML...
Researchers have found that rocky exoplanets which formed early in the life of the galaxy seem to have had a greater chance of developing a magnetic field and plate tectonics than planets which formed later. As both these conditions are considered favourable to the development of life, this means that if life exists in the Galaxy, it may have developed earlier than later, and that planets formed more recently may have less chance of developing life.
As lead scientist, planetary researcher Craig O'Neill said,
"Plate tectonics is important for habitability, and it looks like the optimum conditions plate tectonics existed for planets forming early in the galaxy's lifespan, and may be unlikely to easily recur. For life, maybe that was as good as it gets".
Exoplanets - planets in orbit around distant stars - have been attracting great interest because of the possibility that some of them may harbour life. Presenting the results at the Goldschmidt geochemistry conference, Professor Craig O'Neill (Director of the Macquarie Planetary Research Centre, Macquarie University) continued:
"Because of the great distances involved, we have a limited amount of information on these exoplanets, but we can understand some factors, such as position, temperature, and some idea of the geochemistry of the exoplanets. This allows us to model how they develop".
Using huge simulations involving hundreds of processors on the Australian National Computing Infrastructure, the team ran the parameters through the ASPECT* geodynamics code, which simulates the development of the interior of planets. O'Neill's group was able to show that many early planets would have tended to develop plate tectonics, which is favourable to the development of life.
He commented: "Plate tectonics act as a kind of thermostat for the Earth creating the conditions which allow life to evolve. The Earth has a lot of iron in its core, and we had assumed that this would be necessary for tectonic development. However we found that even planets with little iron may develop plate tectonics if the timing is right. This was completely unexpected".
The development of plate tectonics has a major knock-on effect. "Planets which formed later may not have developed plate tectonics, which means that they don't have this built in thermostat. This doesn't just affect the surface temperature, this means that the core stays hot, which inhibits the development of a magnetic field. If there's no magnetic field, the planet is not shielded from solar radiation, and will tend to lose its atmosphere. So life becomes difficult to sustain. A planet needs to be lucky to have the right position and the right geochemistry at the right time if it's going to sustain life", said Professor O'Neill.
Researchers know that the overall chemical balance of the Galaxy has changed over time for diverse reasons, such as material coalescing into stars and planetary bodies, or being expelled through supernova. This means that the interstellar material available to form planets is significantly different to that available in the early galaxy.
"So the planets which formed earlier did so in conditions favourable to allow the development of life" said Craig O'Neill, "These conditions are becoming increasingly rarer in our galaxy."
Commenting, Professor Sara Russell said:
"Over the last few years, amazing projects such as the NASA Kepler mission have located thousands of planets orbiting around other stars. However, these exoplanet observations alone provide very basic information. It is so important to combine observing campaigns with large simulation projects like this, that really tell us something about the geological evolution of planets formed at different stages of galactic evolution. This enables us to build a picture of what these strange worlds might look like, and how habitable they may be".
Sara Russell is a member of the Scientific Committee of the Geochemical Society. She is Professor of Planetary Sciences and leader of the Planetary Materials Group at the Natural History Museum, London. She was not involved in this work, this is an independent comment.
As of 5th June, NASA has confirmed the detection of 4158 exoplanets in our galaxy, see https://exoplanets.nasa.gov/ . The closest exoplanets yet found orbit the star Proxima Centuri, which is about 4 light years from Earth (latest data indicates either 2 or 3 exoplanets).
The Goldschmidt conference is the world's main geochemistry conference, hosted by the Geochemical Society and the European Association of Geochemistry. Held annually, it covers such material as climate change, astrobiology, planetary and stellar development and conditions, chemistry of Earth materials, pollution, the undersea environment, volcanoes, and many other subjects. For 2020 the scheduled Hawaii congress has been moved online, and takes place from 21-26 June, see https://goldschmidt.info/2020/index. Future congresses are in Lyon, France (2021) and the rescheduled Hawaii congress (2022).
*NOTE: See Advanced Solver for Problems in Earth's ConvecTion https://aspect.geodynamics.org/ ASPECT was developed by the University of California (Davis) with funding from the National Science Foundation.
